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1.
Elisabeth Ofner Jürgen Rheinlaender Heiner Römer 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2007,193(3):321-330
The ability of the bushcricket Leptophyes punctatissima to orient to elevated sound sources was investigated. Males were placed on a walking compensator and oriented in response
to a synthetic female reply, which was broadcast via one of five loudspeakers placed at elevations of 0°, 30°, 60°, 75° and
90°. Forward and backward movements were compensated, so that males remained at the same distance and elevation to the sound
source. With increasing loudspeaker elevation, the males meandered more, and the ratio of the ideal path length to the actual
path length decreased. The same was true for the correlation between stimulus angle and turn angle, and there were more turns
to the wrong side with increasing loudspeaker elevation. Most males performed phonotaxis with a high acuity up to an elevation
of 60°. Individuals varied strongly in their performance especially at a source elevation of 75°, where some were still very
accurate in their approach, whereas the acuity of others decreased rapidly. We also describe a behaviour where males tilt
their body axis to more anterior and sideward positions, both during walking and while calling on the spot. This behaviour
is interpreted as a kind of directional scanning in order to actively induce changes in binaural cues. 相似文献
2.
Konstantinos Kostarakos Jürgen Rheinlaender Heiner Römer 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2007,193(11):1115-1123
We examined peripheral and central nervous cues underlying the ability of the bushcricket Leptophyes punctatissima to orient to elevated and depressed sound sources broadcasting the female acoustic reply. The peripheral spatial directionality
of the ear was measured physiologically using monaural preparations of an auditory interneuron (T-fibre). In the azimuth,
maximal interaural intensity differences of 18 dB occur between ipsi- and contralateral stimulation. With increasing elevation
or depression of the sound sources, IIDs decrease systematically and reach zero with the source exactly above or below the
preparation. Bilateral, simultaneous recordings of the activity of the pair of interneurons allowed determining the binaural
discharge differences which occur in response to the extremely short (1 ms) female reply. These discharge differences are
large (four action potentials/stimulus) and reliable in the azimuth with lateral stimulation, and decrease gradually with
more frontal stimulation. With elevation and depression of sound sources these differences again decrease to one action potential/stimulus
at 60° or 75° elevation, and lateral stimulus angles of about 60°. We also calculated the reliability with which a receiver
could correctly determine the location of the sound source. We discuss these quantitative measures in relation to the spatial
phonotactic behaviour of male L. punctatissima. 相似文献
3.
To understand the relationship between song perception and stimulus location, Bengalese finches were trained to discriminate
between a normally played conspecific song and the reversed song. Loudspeakers on the opposite side of the response key (experimental
condition) and above the subject (control condition) were used to present stimuli. All control birds learned the task, whereas
some experimental subjects did not. In general, controls learned the task more quickly than experimental animals. These results
suggest that sound location may be closely associated with behavioral responses in this species. Bioacoustical investigations
should be performed while taking these results into consideration. 相似文献
4.
There are three most important bacterial causative agents of serious infections that could be misused for warfare purposes:
Bacillus anthracis (the causative agent of anthrax) is the most frequently mentioned one; however, Fracisella tularensis (causing tularemia) and Yersinia pestis (the causative agent of plague) are further bacterial agents enlisted by Centers for Disease Control and Prevention into the category A of potential biological weapons. This review intends to summarize basic information about these bacterial
agents. Military aspects of their pathogenesis and the detection techniques suitable for field use are discussed. 相似文献
5.
The life cycle and developmental stages of Aylax hypecoi (Trotter, 1913, Hymenoptera: Cynipidae: Aylacini) were studied in detail. Aylax hypecoi is known to induce galls in fruits of two Hypecoum species — H. imberbe and H. geslini (Papaveraceae) and the larva develops in host plant fruits. The morphology and development of egg, larva and pupa were investigated, which
has previously not been done. The shape and size of terminal-instar larvae and associated galls are sex-specific. Overwintering
stage, adult emergence and flying periods, and egg productivity were studied also. 相似文献
6.
S. E. Dawson 《Kew Bulletin》2008,63(3):517-517
Summary The name Pavetta modesta (Hiern) S. E. Dawson is a later homonym of P. modesta Bremek. Pavetta crystalensis is proposed as a new name. 相似文献
7.
Dmitar Lakušić 《Biologia》2008,63(5):631-636
The south-European Cardamine plumieri Vill. (sect. Pteroneurum subsect. Cryptopterum) is confirmed for the Flora of Serbia. Several populations were discovered in the central and western part of country, exclusively
on the serpentine bedrocks. Morphological, chorological and ecological characteristics of C. plumieri was studied. 相似文献
8.
Summary. The paper describes two methods of the synthesis of ethyl (3R,4S)- and (3S,4S)-4-[(benzyloxycarbonyl)amino]-5-[(tert-butyloxycarbonyl)amino]-3-hydroxypentanoates, useful for the syntheses of edeine analogs. Differently N-protected (S)-2,3-diaminopropanoic acid was used as a substrate in both procedures. The absolute configuration of newly generated asymmetric
carbon atoms C-3 in β-hydroxy-γ,δ-diamino products was assigned by means of 1H NMR spectroscopy after their transformation into corresponding piperidin-2-ones.
Received May 24, 2002 Accepted October 10, 2002 Published online December 18, 2002
Acknowledgment The authors are indebted to the Faculty of Chemistry, Technical University of Gdańsk for financial support.
Authors' address: Zbigniew Czajgucki, M. Sc., Department of Pharmaceutical Technology and Biochemistry, Faculty of Chemistry, Technical University
of Gdańsk, 11/12 Narutowicza St., 80-952 Gdańsk, Poland, Fax +48 58 347 11 44, E-mail: zmczaj@wp.pl 相似文献
9.
The research on incidence of mistletoe (Viscum album ssp. abietis) on silver fir (Abies alba) was carried out in natural fir stands in Croatia. In the area of Gorski Kotar 32.8 % of the examined dominant fir trees
were infected with mistletoe. The mistletoe incidence was presented according to the damage degrees of silver fir from 0 (healthy
trees) to 4 (dead trees), rated by the crown defoliation and needle discoloration. With the increase of incidence, mistletoe
spreads more onto more vital, i.e. less damaged trees. In the Dinaric Alps 28.6% of the examined fir trees were infected,
this percentage amounting to 27.1% for the mountainous regions between the Sava and Drava rivers.
The site and stand parameters (exposure, elevation, site quality, forest community and crown closure) were analysed in order
to establish whether there was a correlation between these parameters and mistletoe incidence. There was a negative correlation
between the elevation and mistletoe incidence. Among the compartments with a closed stands there were considerably less compartments
with higher mistletoe incidence than among compartments with a sparsely closed and understocked stands. The other analysed
site and stand parameters individually had no significant influence on mistletoe incidence.
The correlation of silver fir mortality in 2004 and mistletoe incidence in 2002/03 was analysed, and their strong correlation
was established. Mistletoe could be considered as a bioindicator of silver fir decline, and probably a significant contributor
to that decline. In the areas where mistletoe incidence is great it can be presumed that silver fir is significantly damaged. 相似文献
10.
11.
O. V. Golovanova V. I. Konenkov A. V. Shevchenko M. V. Smolnikova 《Russian Journal of Genetics》2009,45(8):981-986
Based on population analysis of the DRB1, DQA1, DQB1 and TNFA allele frequency distribution patterns, regional features of immunogenetic structure of the population of West Siberia were
investigated. Statistically significant linkage disequilibrium within the HLA class II region, as well as between the TNFA and DRB1, DQA1, and DQB1 was demonstrated. Population frequency distribution patterns of two- and multilocus haplotypes were examined. 相似文献
12.
13.
The architecture of the musculature of the eutardigrade species Milnesium tardigradum Doyère, 1840, Hypsibius sp. and Ramazzottius oberhaeuseri (Doyère in Ann Sci Nat Zool Sér 2(14):269–369, 1840) is investigated by phalloidin staining and confocal laser scanning microscopy. There are methodological problems in staining
eutardigrades due to physiological alterations under stress (anhydrobiosis) and due to penetration problems of the cuticle.
It is helpful to fix specimens in the state of asphyxy, where animals are stretched following an oxygen shortage in their
environment. The musculatures of all three species correspond in their general architecture, but differ in detail, such as
in the number of muscles. All muscles are isolated muscle strands. There are on each body side two dorsal and one ventral
muscle strands, in addition to a system of dorsoventral, lateral and lateroventral muscles. Seven median ventral attachment
points give rise to dorsoventral, ventrolateral and appendage muscles. The appendages receive several muscles originating
dorsally and ventrally. The number of muscles and the arrangement differ in each appendage. The fourth appendage shows the
greatest differences with a far smaller number of muscles compared to other species. The musculature shows comparably few
strict segmental patterns, for example, the musculature of each appendage differs from the other ones. By comparison with
literature data on the same species and data of Macrobiotus hufelandi it can be shown that eutardigrades have a roughly comparable muscular architecture, but that there are several differences
in detail.
Dedicated to Professor Westheide on the occasion of his 70th birthday. 相似文献
14.
The intron sequence of chloroplast rpS16 and the secondary structure of its pre-mRNA were characterized for the first time in 26 Allium sativum accessions of different ecologo-geographical origins and seven related Allium species. The boundaries and main stem-loop consensus sequences were identified for all six domains of the intron. Polymorphism
was estimated for the total intron and its regions. The structural regions of the rpS16 intron proved to be heterogeneous for mutation rate and spectrum. Mutations were most abundant in domains II and IV, and
transition predominated in domains I, III, V, and VI. In addition to structural elements and motifs typical for group IIB
introns, several Allium-specific micro- and macrostructural mutations were revealed. A 290-bp deletion involving domains III and IV and part of domain
V was observed in A. altaicum, A. fistulosum, and A. schoenoprasum. Several indels and nucleotide substitutions were found to cause a deviation of the pre-mRNA secondary structure from the
consensus model of group II introns. 相似文献
15.
To overexpress the chitosanase gene (csn) in F. solani, a vector based on pCAMBIA 1300 was constructed. The csn gene, which is under control of the Aspergillus nidulans
gpdA promoter and A. nidulans trpC terminator, was introduced back into the F. solani genome by Agrobacterium tumefaciens-mediated transformation, and the herbicide-resistance gene bar from Streptomyces hygroscopicus was used as the selection marker. Transformants which showed a significant increase in chitosanase production (~2.1-fold
than control) were obtained. Southern blot analysis indicated that most transformants had a single-copy T-DNA integration. 相似文献
16.
Hiroyoshi Kubo 《Mycoscience》2009,50(5):400-406
Pilobolus crystallinus shows unique photoresponses at various growing stages. cDNAs for putative photoreceptors were cloned from this fungus. Three
genes named pcmada1, pcmada2, and pcmada3 were identified from the PCR fragments, and amplified with degenerated primers for the LOV domain, which is conserved in
many blue-light receptors. Deduced amino acid sequences for PCMADA1, PCMADA2, and PCMADA3 had one light-oxygen-voltage (LOV)-sensing
and two PER-ARNT-SIM (PAS) domains. A zinc finger DNA-binding motif was conserved in the C-terminals of PCMADA1 and PCMADA3.
However, PCMADA2 lacked the zinc finger motif. Expression of pcmada1 was suppressed by blue light whereas that of pcmada3 was promoted by blue-light irradiation. 相似文献
17.
Michael G. Boegle Susanne Schneider Beate Mannschreck Arnulf Melzer 《Hydrobiologia》2007,586(1):155-166
18.
Reinerio Benega Garcia Aroldo Cisneros Bert Schneider Noemi Tel-Zur 《Plant cell reports》2009,28(5):719-726
Gynogenesis was investigated on the allotetraploid Selenicereus megalanthus and the diploid Hylocereus polyrhizus and Hylocereus undatus vine cactus species. Unpollinated ovules from developing flower buds containing microspores at middle uninucleate developmental
stage were cultured on MS basal medium containing 2,4-D/TDZ with different sucrose concentrations. Ovule size increased under
dark culture conditions in all the three species and the level of response was species and sucrose concentration dependent.
The best responses were achieved in the two S. megalanthus accessions, E-123 and J-80, at 0.18 and 0.26 M sucrose. Only ovule enlargement was obtained in H. undatus and both ovule enlargement and callus were obtained in H. polyrhizus. Development in both species ceased and embryoids were not formed. Plant regeneration was directly and indirectly obtained
in both S. megalanthus accessions. Ploidy level was determined for a total of 29 S. megalanthus gynogenic plants using flow cytometry: 15 were found to be dihaploid (plants with the gametophytic chromosome number) and
the other 14 were found to have higher ploidy levels. This is the first report of successful gynogenesis in Cactaceae. The
dihaploids of S. megalanthus successfully produced by ovule culture techniques opens new perspectives in vine cacti breeding. 相似文献
19.
20.
Philomena Bodensteiner 《Mycological Progress》2007,6(4):221-228
Maireina afibulata and M. attenuatipilis are proposed as new members of the recently revised genus Maireina, one of the few anatomically well-studied cyphelloid groups in the Basidiomycota. Maireina species have brownish basidiomes, smooth, parietally unpigmented spores, and are characterized by non-ramified external hyphae
with more or less thick, yellow to brown cell walls and distinct crystalline incrustations that always include their distal
ends. A key to the species of the genus Maireina is presented, and M. afibulata as well as M. attenuatipilis are described and discussed in detail.
Taxonomic novelties: Maireina afibulata Bodensteiner, M. attenuatipilis Bodensteiner 相似文献